It is exciting that the gravitational wave (GW) GW150914 [1]} was detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015, which demonstrates the existence and merging of a binary stellar-mass black hole (BH) system for the first time. Since then, a new window has been opened to observe the Universe. It was shown in Ref. [2]} that GW astrophysics can become a precision discipline without being spoiled by various astrophysical environmental effects.
